头颈肿瘤中干扰素α在诱导肿瘤杀伤高活性的中性粒细胞转化中的作用及机制

Neutrophils have showed a great therapeutic potential in the many tumors including head and neck squamous cell carcinoma, as a promising new immunotherapy strategy. Depending on the different cancer-killing activity (CKA), neutrophils can be classed into two groups: the high CKA (N1) group and Low CKA (N2) group. Under the certain condition, the polarization of N1 and N2 can occur, which decreased the cancer killing activity of N1 neutrophils, and limit its clinical application. Up to date, it is unclear about the mechanism of polarization of N1 and N2 neutrophils. Our previous RNA –seq data showed that the polarization N2 to N1 neutrophils can be induced by IFN-a and CXCR4 plays a critical role in this signal pathway. Therefore, in order to elucidate the role of IFN-a in polarization of N1 versus N2 in HNSCC, we plan to use a series of methods to study its mechanism at histological, cellular and molecular level, respectively, including Mass Spectrum, pathway interfering and cancer cell killing assay, and also to understand the developmental process of in polarization of N1 and N2 neutrophils by inhibiting CXCR4 signaling pathway. This study will not only help us to find the key candidate target molecules to obtain a large amount of N1 neutrophils, but also provide new understanding and new theory for the cancer immunotherapy for HNSCC patients in clinic.

新近发现中性粒细胞在肿瘤细胞免疫治疗中起重要作用，在头颈鳞癌等多种肿瘤治疗中具有很好的应用前景，根据其肿瘤杀伤活性分为N1（高活性）与N2 （低活性）型，特定环境下可发生N1与N2型转化，降低其肿瘤杀伤活性，从而限制了其临床应用。目前关于N1与N2型转化调控机制尚不清楚。我们前期分析了RNA-seq数据，发现IFN-α的表达与中性粒细胞转化相关，可调控其对肿瘤细胞的杀伤活性，还发现IFN-α表达和N1与N2型转化关键信号通路CXCR4密切相关。由此我们推测IFN通过影响下游CXCR4通路的活性调控中性粒细胞转化进程。因此 项目拟采用质谱分析、通路干预、细胞杀伤活性检测等技术，明确IFN-α在头颈鳞癌N1与N2型中性粒细胞转化中的调控作用，阐明其通过抑制CXCR4通路活性调控细胞转化进程，以期获得中性粒细胞转化的关键干预靶点，为中性粒细胞头颈肿瘤免疫治疗的方法优化、效果提高提供新理论新方法。

中性粒细胞在肿瘤细胞免疫治疗中起重要作用，在多种肿瘤治疗中具有很好的应用前景，根据其肿瘤杀伤活性分为N1（高活性）与N2 （低活性）型，特定环境下可发生N1与N2型转化，降低其肿瘤杀伤活性，从而限制了其临床应用。目前关于N1与N2型转化调控机制尚不清楚。我们前期分析了RNA-seq数据，发现IFN-α的表达与中性粒细胞转化相关，可调控其对肿瘤细胞的杀伤活性，本项目执行过程中，围绕N1与N2的转化，及N1杀伤肿瘤的机制，综合运用流式细胞、RNA-seq，细胞杀伤活性检测，实验动物学、结构生物学等技术进行了系统性研究，并取得多项研究成果：1）发明一种诱导人体中性粒细胞的杀伤肿瘤细胞活性方法（申请号或专利号：20190333409.8）；2）阐明粒细胞杀伤肿瘤的作用机制；3）正常人体分离的N1型粒细胞在荷瘤鼠的体内分布器官与动力学；4）发明一种新的粒细胞体外冻存液可以将粒细胞期延长并保持其细胞杀伤活性；5）开展膜蛋白结构研究，并用冷冻电镜技术解析重要膜蛋白复合物NDH-1L的结构（nature communications, 已接收）。为中性粒细胞肿瘤免疫治疗的方法优化、作用机制、效果提高提供新理论新方法。